Enhanced adherence of diamond coatings
AssigneeTrustees of Boston University
InventorsVinod K. Sarin, Shish P. S. Arya
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Abstract
This invention is directed to the creation of diamond coatings with enhanced adherence on substrates, such as tungsten carbide-cobalt (WC--Co), by chemical vapor deposition. This process comprises the steps of creating a combustion flame, supplying a deposition promoter to the flame, positioning a substrate into the flame, and forming the diamond deposit with enhanced adherence on the substrate. The invention is also directed to methods for the formation of a diamond deposit with enhanced adherence by the addition of a high-temperature binder such as a refractory metal or an organometallic compound. Once incorporated, the high-temperature binder acts as a cement which increase the strength and adhesion of the coating to the substrate.
Claims19
A crystalline diamond coated substrate wherein a coating is deposited on the substrate by establishing a flow of oxygen and acetylene to a combustion device at a volumetric flow ratio (R=O.sub.2 /C.sub.2 H.sub.2) of greater than or equal to about 1.0;
- creating a flame in the combustion device, wherein the flame comprises an inner core region, an acetylene feather region, and an outer region;
- positioning the substrate, which is maintained at a temperature of between about 300.degree. C. to about 1200.degree. C., in the acetylene feather region;
- adding to the flame a deposition promoter to favor the growth of a strongly adherent, uniform layer of crystalline diamond particles on the substrate, wherein the deposition promoter is selected from the group consisting of carboxylic acids, alcohols, aldehydes, ketones, ethers and carboxylic acid esters;
- and depositing the strongly adherent, uniform layer of crystalline diamond particles of substantially uniform size and shape on the substrate.
A crystalline diamond-coated substrate wherein a coating is deposited on the substrate by establishing a flow of oxygen and acetylene to a combustion device at a volumetric flow ratio (R=O.sub.2 /C.sub.2 H.sub.2) of greater than or equal to about 1.0;
- creating a flame in the combustion device, wherein the flame comprises an inner core region, an acetylene feather region, and an outer region;
- positioning the substrate, which is maintained at a temperature of between about 300.degree. C. to about 1200.degree. C., in the acetylene feather region;
- adding to the flame a high-temperature binder which is a refractory metal or an organometallic compound;
- and depositing the layer of crystalline diamond particles on the substrate which is bonded to the substrate by the high-temperature binder.
Dependencies are inferred from the claim text.